Company History

After our company was established in 1950 production started in 1951. The 400-year-old experience of the family Diederichs in the forging industry served as a solid foundation. 

Production commenced with six employees. The number and efficiency of the forging presses was continuously increased, the company grounds extended and new workshops and administration buildings built. 

Beyond traditional forging presses, investments were made in ring-rolling mills, heat treatment and mechanical machining equipment and quality assurance in order to extend the product and manufacturing range. 

In 1991 Hammerwerk Erft was certified according to DIN/ISO 9002 – EN 9002 and became the first open-die forge in Germany not part of a group to receive this award as a result of the consistent focusing on quality improvement and error minimization. 

In April 2002 we were able to confirm our high standards and our leading role in quality assurance by certification in accordance with ISO 9001:2000. 

In recent years, Hammerwerk Erft has been regularly re-certified according to EN ISO 9001:2000, and most recently in March 2008. 

Between 2002 and 2006, investment in replacements and extensions were carried out in all areas of the company and a number of new approvals obtained (e.g. for the production of safety-related products for international nuclear plants). 

After long preparations and an extensive approval process, work began on expanding the mechanical processing workshop and heat treatment plant in late summer 2006. Meanwhile, the primary material store was extended by way of a storage area with gantry crane.

The new turnery hall was put into operation in early 2007 and offers plenty of space for more machinery. Additional ultrasonic testing stations were also installed here.    

The construction work for the extension of the heat treatment system was completed in spring 2007. In mid-2007 the first new furnace, with a capacity of 75 tonnes, began operation. 

In late 2007, the largest single investment process in the company's history commenced: the construction of a new press hall with a 3,500-tonne open die forging press and several forges. In order to create this space, the employee parking area and the primary materials store had to be relocated. 

Since 2010, Hammerwerk Erft has been certified according to EN ISO 9001:2008 

At any time our company has been well-known for its excellent products, quality and service and is one of the leading companies in the forgings business. 

Our main priority is to satisfy our customers with best possible product quality, service and flexibility. Particularly forgings subjected to high loads with unusual specifications are our strong point which is proved by our long-standing business relations with our satisfied customers. 

Our company is well prepared for the future with modern equipment and constant striving for cost optimisation and quality improvement.

Frachtbrief von 1882
Frachtbrief von 1882


  • 16th. century: Ancestors of the family Diederichs begin practising the forging handicraft
  • End of the 40's: Acquisition of land
  • 1950: Establishment of the company
  • Late summer 1950: Commencement of production with six employees and a 400 kg air hammer
  • 50's and 60's: Installation of further forging presses
  • End of the 60's: Building of a boiler house 2000 kg hammer 3000 kg hammer 1969: First ring-rolling mill
  • In the early 70's: 1000 ton press; Building of our heat treatment shop
  • 1991: Certification according to DIN EN ISO 9002
  • 1999: Building of the new turnery
  • End of 2000: New ring-rolling mill RAW 160/160
  • 2002: Certification according to EN ESO 9001:2000 
  • 2002 - 2006: Investment in all company areas Various new accreditations
  • 2006 - 2007: Construction of another turnery
  • Expansion of the heat treatment plant Primary material store with gantry crane
  • 2008: Construction of new press hall 
  • 2010: Certification according to EN ISO 9001:2008
  • 2010: Certification according to EN ISO 14001:2004
  • 2012: Construction of new oil-hardening tank
  • 2013: Certification according to EN ISO 50001:2011
This website uses functional cookies to enable easy accessability to the webpages. By accessing the content of this website you agree to the utilisation of cookies. Privacy Statement